Dishwashing machine



Oct. 6,1953 Q SWAY DISHWASHING MACHINE 3 Sheets-Sheet 1 Filed Feb. 9,1949 Inventor: Henry C. Swag, M

Hi5 Attorney H. C. SWAY DISHWASHING MACHINE Oct. 6, 1953 3 Sheets-Sheet2 \nventow Henry C. sway.

His Attovney.

Filed Feb. 9, 1949 x M k x llllltilllllllli \M|I..||||| A 1 v 1953 H. c.swAY DISHWASHING MACHINE 3 Sheets-Sheet 3 Filed Feb. 9, 1949 HisAttorney.

3 dropped during the loading of the machine, from fouling the impeller.

In a dishwasher of the impeller type, it is preferable to arrange themotor 21 so that its shaft 4| will extend vertically upwardly concentricwith the tub 28. A sleeve or bearing 42 for the motor shaft may beintegral with and extend upwardly from the lower wall 43 of the pumpchamber 44. It will be understood that suitable seals (not shown)protect against contamination of the wash water with lubricant andprevent water from passing into the motor. Advantageously, the pumpchamber is formed as part of the motor housing and afiords means ofsecuring the housing to the bottom of the tub, as by screws 45 orequivalent. It will be understood that gaskets and otherleakage-preventing means are provided to seal the aperture at the bottomof the tub. Sleeve 42 extends upwardly to a point substantially abovethe static water level, WL, and at its upper end is provided withsuitable water sealing means (not shown). Fixed to the upper end of theshaft ll is a tubular hub'structure 46 which extends about the bearing42 in concentricity therewith. Suitably secured to hub it-advantageouslyintegral therewith-is a pump impeller 4'! which, as later explained,pumps water outwardly through the discharge conduit 48 to the dischargecontrol valve 50 and thence to the drain connection 2 3. Also afiixed tothe motor shaft and carried by the upper end of the pump hub is the hubSI of the impeller 52. The impeller and its hub may be molded fromrubber compounds or plastic materials which are satisfactorily abrasionresistant. The impeller blades have a sharp angle of attack as isapparent in Fig. 2 and the motor and impeller are capable of substantialwater movementfor example, at the rate of 50 gallons per minute.

A present embodiment of a dishwasher embodying the present inventionoperates most satisfactorily on one gallon of water, said quantityfilling the lower portion of the tub to a point wherein the impeller 52is approximately onehalf submerged. A feature of the invention residesin the use of a chamber associated with the cover to measure the waterwith substantial accuracy. As appears to best advantage in Fig. 2 thewater chamber may be formed by the cover itself, by making the cover ofhollow construction, in which an upper member 53 which is shaped to forma convex top wall and cylindrical side wall cooperates with a contouredbottom wall 54 suitably secured to the member 53. Preferably the pointof securement is at an outwardly extending peripheral lip 55 which formsan anchor for gasket 55 which seats on a ledge 51 of the tub when thecover is closed. The central portion of the bottom wall 54 is domed asat 58 and at its center is provided with an opening 59. Said opening ispartly closed by a baffie 60 which is supported by a bracket 6| afifixedto the cover member 53, said shield having any desired number of sidewall openings 69a. The inflow hose 23 seats telescopically about a rigidinlet pipe 62 which enters a side wall of an upper hinge cover plate 63,and then extends into the cover chamber, terminating at any suitablelocation therein. In the illustrated embodiment the pipe 52 isillustrated as being in contact with the underside of the cover member52, thereby being suitably above the maximum cover water level, C. W.L., to provide an air gap sufficient to prevent back siphonage from thecover to the fill line. The end of the pipe may be bafiled or the pipeprovided with bridge means or the like for supporting it within thecover, as a matter of choice. As best appears in Fig. 3 an opening inthe bottom cover member 54 is provided with a plate-like structure 64which defines a valve seat 65 extending upwardly into the cover. Saidvalve seat cooperates with a valve disk 66 to permit the cover chamberto be filled, or drained into the tub according to the operatingposition of the disk. An open-topped detergent cup or container 6'! fitssnugly against the underside of plate 64, and forms a conduit throughwhich water flows from the cover into the tub. Suitable side wallchannels of container 6! (not shown) engage with side tracks (58 toremovably support the container 6! on the plate M. Preferably, the cupis of molded plastic or like lightweight material.

The filling and draining of the cover chamber is controlled by a slidingvalve operator iii having an end portion which extends upwardly througha slot in the cover handle II, to terminate in' a suitable knob 12. Abracket 13 provides a supporting saddle M for the rod 10 and also adetent plate 15 for cooperation with the roller- 7 provided detentmember 16 afiixed to the vertical portion of rod 18.

Such construction is detailed in Fig. 5. As is apparent from Fig. 3 thedetent rollers will climb over the shoulders formed in detent plate 15during movement of the valve rod to the left or right and seat in theadjacent valley to retain the valve rod in one or the other position. Itis understood, of course, that the detent member 16 is springable so asto permit the rollers to ride over the shoulders. Valve disk isadvantageously supported on on arm 11 having an apertured head structurethrough which the mushroom end 18 of the valve disk structure extends.The valve disk structure has a suitable degree of adjustment relative tothe arm l! to insure secure seating on seat 66. Arm TI is biased intorotation in valve seating direction by such means as a leaf spring 80suitably secured as suggested in Fig. 3. The leaf spring forms thedouble function of biasing the valve as aforesaid and supporting it inproper position relative to the valve seat. Arm 1! is forked atits upperend to slidably receive the rod 10, said rod having a short cross pin 8|which is immediately to the right of the arm 11 as viewed in Fig. 3. Itis obvious that when the control knob 12 is pushed leftwardly to thedotted position of Fig. 3, the pin 8| will enforce a counterclockwiserotation of the arm 11 to unseat the valve disk 61 and thereupon permitthe water to drain into the tub. It will be noted that the cover isvented through one or more ports 82 so that drainage will be free andunimpaired. The vent ports may be covered by suitable rearward extension83 of the handle H. As appears best in Fig. 1 the extension 83 providesa suitable plurality of relatively narrow air inflow passages.

' orifice I I6 through which the water flows to the impeller. The ringtherefore meters water flowing to the impeller, and prevents anysubstantial amount reaching the impeller above the base thereof. Themetering ring effectively reduces the surging which occurs if the wateris allowed to circulate freely into the impeller. It will be noted thatthe ring fits relatively closely about the impeller, at the low point ofthe bottom of the tub. Thus, after the quantity of water within the ringhas been thrown upwardly by the impeller, water flows to the impellersubstantially only through the orifice HE. A metered flow of water tothe base of the impeller is thereby enforced. The metering ringeffectively reduces the critical effect of the quantity of water withinthe tub. It has been demonstrated that the water quantity may bedoubled--increased to two gallonswithout overloading the motor.

After the desired washing period the tub is drained by returning thecontrol handle to the fill-drain position. The movement of the controlrod 10 lifts the valve stem 82 so that the valve disk assembly of thedischarge valve 50 is free to lift. It should be understood that allduring the washing operation the pump impeller 41 has been rotatinginasmuch as it is fixed to the motor drive shaft 4] in common with theimpeller hub However, the outlet valve 50 has been held closed by meansof the spring 92 and the pump impeller has been rotating idly within thepum chamber; but as soon as the valve stem 92 is raised the pumppressure lifts the valve disk and permits water to flow outwardlythrough the connection 24 to the discharge port of the faucet fitting.To improve the flow of water into the pump casing, I form the pump cover502, see Fig. 10, with a central cavity or sump I II at the center ofwhich is an upwardly extending circular wall I I8. Extendingtangentially from said wall to the periphery of the cover are vanes I2and l2l, said vanes being approximately the height of the wall H8. Inthe cover portion defined by the two vanes I20, I2I the pump cover isslotted to provide an arcuate inlet port I22 at the base of the circularwall II 8. In the space between vane I2I and a third tangentiallyextending vane I23 there is no bottom wall opening because said space isadjacent to the discharge or high pressure area of the pump housing.Accordingly, vane I23 terminates short of the ring H8 to provide a flowpassage I24 into a cover area defined by the vanes I23 and I20, in whicharea there is another slot, I25, communicating with the pump chamber.I22 and I25 are in the low pressure area of the pump chamber farthestremoved from the discharge port. The slot size is such that water willdrain rapidly from the tub, but objects which might damage the pump areprevented from entering.

Centrifugal pumps previously used with dishwashing machines and the likehave had an inlet openin or openings extending about the full hubcircle. In such constructions, noisy splashing and expulsion of wateroccur through the opening every time a pump blade passes the cutoffpoint at the outlet. In dishwashers, this undesirable characteristic ismost apparent when the pump is operating at the end of the drain cycle.It should also be considered that in dishwashers, this splashing andnoise could be of considerable magnitude, for in adapting a centrifugalpump to a desired tub construction it is impossible to have the inletpassage at the very cen- It will be apparent then that the slots ter ofthe pump cover as in the conventional centrifugal pump design. My pumpcover construction as shown herein substantially eliminates thesplashing and expulsion of water by blanking off the pump cover over thehigh pressure area of the pump, as explained above. The present pumpcover also provides an improved inflow condition at the pump inlet; thetangential vanes nullify the natural vortex action of the incoming waterwhich might otherwise detract from the proper functioning of the pump.The absenc of an inlet port adjacent to the high pressure cutofi pointprevents a conflicting flow of water, thus also minimizing the noisewhen operating with only residual water in the pump cavity.

The operation of the outlet valve is particularly effective in that thefree action of the valve seat assembly operates as a check when themotor is stopped, to prevent the water in the drain tube 48 from flowingback into the pump cavity and the bottom of the tub. At the end of thedrain cycle when the last of the water is being emptied from the tub,air begins to enter the pump. At this moment, the tube 48 is full ofwater by virtue of the pressure created by the revolving pump bladesaccelerating the water. Air, however, cannot be accelerated with equalfacility by the pump blades and the pressure at the base of thisvertical water column falls off. Without the free Valve seating actionof the valve 50, water would drain back into the pump chamber untilenough water (and resultant pressure) accumulate to again force thewater up the tube. A cyclic surging action would result, creating anoise that would be disturbing to the operator. However, the valve seatis free to close when the Water flow ceases and by preventing air fromentering, the water is held in tube 48 until enough pressure is createdby the pump to lift the valve seat assembly. Thus, although the finaldrainage from the tub may be intermittent, the disconcerting surgingnoise is not present.

While I have shown a particular embodiment of my invention, it will beunderstood, of course,

that I do not wish to be limited thereto since many modifications may bemade; and I therefore contemplate by the appended claims to cover anysuch modifications as fall within the true spirit and. scope of myinvention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In a dish washing machine, a tub having a depending bottom wallportion at its lower end which defines an impeller chamber, an impellerin said impeller chamber for circulating water from such chamberthroughout the tub and from which it flows back to such chamber, aclosure for the upper end of the tub having top and bottom walls whichdefine a water chamber, a. wall projecting upwardly from said bottomwall which defines an overflow passage through said bottom wall andserves to define a liquid level in said water chamber, an opening insaid bottom wall through which liquid in said water chamber may flowdirectly to said impeller chamber whereby a volume of wash watermeasured in' said water chamber may be supplied to said impellerchamber, a discharge conduit connected to the bottom of said impellerchamber, an inlet valve for closing said opening, means connected withsaid valve for opening and closing it, and a conduit connected to saidwater chamber through which water may be supplied to it.

2. In a dish washing machine, a tub having a a ree conical bottom wallportionatrits lower endwhich; cflaesam mpeHe e ,-,an-.-im e1 er-in saidimpeller; chamber for circulating water from-such chamberthrpughout thetub and-from which. it flaws a tozsu h mber, at lqsure fom heppgreendoigthe tub havingtqp and bottom :wa ls whi htd neza w t r mb rcwa present n upwardly ,irom said bottom wall which defines-an overflowpassage through said bottom wall- ;and env sito defin al quid l velrin ad w erscham bet; :anzopening in said bottom'wall,throughrwhich liguid insaid watcr chamber may flow; directly toizsaid impeller chamber wherebya volumeof washwater measured in said water-chambermay be supplied to,saidimpellerphamber, a discharge conduit connected -'-to the bot-tom'ofsaid impeller chamber, an inlet valvetforclosin said openinanwoutletwalve. .for, .theidischargeiconduit; ,means connected to: said..valves which when \onerated effects the opening of one of said valvesand the closing of the other, and a conduit connected to said waterchamber through which water may be supplied to it.

3. In a dishwashing machine, a tub having a depending bottom wallportion at its lower end which defines an impeller chamber, an impellerin said impeller chamber for circulating water from such chamberthroughout the tub and from which it flows back to such chamber, ahinged closure for the upper end of the tub having top and bottom wallswhich define a water chamber, a wall projecting upwardly from saidbottom wall which defines an overflow passage through said bottom walland serves to define a liquid level in said water chamber, an openin insaid bottom wall through which liquid in said water chamber may flowdirectly to said impeller chamber, whereby a volume of wash watermeasured in said water chamber may be supplied to said impeller chamber,a detergent receptacle connected to the under side of said bottom wallin line with said opening, a discharge conduit connected to the bottomof said impeller chamber, an inlet valv for closing said opening, meansconnected with said valve for opening and closing it, and a conduitconnected to said water chamber through which water may be supplied toit.

4. In a dish washing machine, a tub having an impeller chamber at itslower end, an impeller in said impeller chamber for circulating waterfrom such chamber throughout the tub and from which it flows back tosuch chamber, a closure for the upper end of the tub having top andbottom walls which define a water chamber, a wall projecting upwardlyfrom said bottom wall which defines an overflow passage through saidbottom wall and serves to define a liquid level in said water chamber,an opening in said bottom wall through which liquid in said waterchamber may flow directly to said impeller chamber whereby a volume ofwash water measured in said water chamber may be supplied to saidimpeller chamber, a drain pump having its inlet connected to the bottomof said impeller chamber, a discharge conduit which extends upwardlyalong the side of said tub with its lower end connected to the drainpump outlet, an inlet valve for closing said opening, an outlet valvefor the upper end of the discharge conduit, means connected to saidvalves which when operated effects the opening of one of said valves andthe closing of the other, and a conduit connected to said water chamberthrough which water may be supplied to it.

5. In a dish washing machine, a tub having an open top, a hinged coverfor the open top com- 1&6 primer-t p; and-bat en wa ls. wl cha efinse aWaterichamben means taic tm lunwardlyi r mi said bottom; wall; Whhtdefiues, anhov rhoiv pen whereb aameasure ivo umee t, Water. ay esupplied ,torsa d. Water hamber, a bane plateeca ried.by;s idcbqttomnalli beneath. said: overflow opening for distributing water overflowingtherethrough over dishes in said tub whereby ermay b ,eiv n,..an inital.. a botto chamber, an'impeller initheiimpellenchamber for circulatingwater over dishes in;the tub, angopen ing, inlthe,bottom wall ofthe,cover; throug=h:Which a volume ot water measured inth'e water1 hbemmag be supplied directly,,tothecimpeller chamber, a valve forclosing,saidmpening means for? operating said valve, a water supplyconduit enn c e -do said water chambe andchargeicpnduit connected totheebottom;-, impeller chamber.

6. In a dish washing machine, a tub having an open top, a hinged coverfor the open top comprising top and bottom walls which define a waterchamber, a water supply conduit connected thereto, means projectingupwardly from said bottom wall which defines an overflow opening wherebya measured Volume of water may be supplied to said water chamber, abottom wall for the tub shaped to define an impeller chamber, animpeller in the impeller chamber for circulating water over dishes inthe tub, a supply opening in the bottom wall of the cover through whicha volume of water measured in the water chamber may be supplied directlyto the impeller chamber, a drain pump having its inlet connected to thebottom of the impeller chamber, a discharge conduit for the pump, thedischarge end of which terminates adjacent to said cover, an inlet valvefor closing said supply opening, a discharge valve for closing the endof said discharge conduit, and an operating member carried by the coverfor controlling said valves which when moved to one position effects theopening of one of said valves and the closing of the other and whenmoved to another position effects the opening of the other of saidvalves and the closing of the one valve.

'7. In a dish washing machine, a tub having an open top, a hinged coverfor the open top comprising top and bottom walls which define a, waterchamber, a water supply conduit connected thereto, means projectingupwardly from said bottom wall which defines an overflow opening wherebya measured volume of water may be supplied to said water chamber, abottom wall for the tub shaped to define an impeller chamber, animpeller in the impeller chamber for circulating water over dishes inthe tub, a supply opening in the bottom wall of the cover through whicha volume of water measured in the water chamber may be supplied directlyto the impeller chamber, a drain pump having its inlet connected to thebottom of the impeller chamber, a discharge conduit for the pump, thedischarge end of which terminates adjacent to said cover, an inlet valvefor closing said supply opening, a discharge valve for closing the endof said discharge conduit, a valve control member which in one positionholds the discharge valve closed and in another positionpermits it to beopened by pressure in the discharge conduit, and an operating membercarried by the cover for controlling said inlet valve and said valvecontrol member which when moved to one position effects the opening ofsaid inlet valve and move- 1 1 ment of said valve control member toclose the discharge valve and when moved to another position efiects theclosing of the inlet valve and the movement of said valve control memberaway from said discharge valve whereby it may be opened by pressure insaid discharge conduit.

HENRY C. SWAY.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 954,879 Ostrom Apr. 12, 1910 1,105,561 Hershey July 28, 19141,196,862 Hayes Sept. 5, 1916 1,487,426 Andrews Mar. 18, 1924 1,505,492Reddig Aug. 19, 1924 1,645,815 Murdoch Oct. 18, 1927 1,722,272 Buck July30, 1929 Number Number Name Date Dunham May 13, 1930 Pauly Oct. 25, 1932Pauly Oct. 25, 1932 Snyder et a1 Mar. 26, 1935 Stoddard May 21, 1935Chandler June 13, 1939 Clark et al Sept. 2, 1941 Moody May 12, 1942Balcunas June 23, 1942 La Bour July 28, 1942 Ballentine Feb. 29, 1944Voris Dec. 11, 1945 Loeb Feb. 26, 1946 FOREIGN PATENTS Country DateGreat Britain Nov. 5, 1937 Switzerland Sept. 15, 1949

